This invention relates to a water purifying apparatus for purifying raw water such as tap water and groundwater to provide purified water for domestic or business use.
A conventional water purifying apparatus comprises a tank for storing raw water such as tap water and a chlorine generator placed in the tank for generating hypochlorous acid. The tank is generally called a cistern in the art. The chlorine generator comprises a pair of electrodes which are arranged parallel to each other to serve as an anode and a cathode known in the art. It is assumed that the tap water contains chlorine ions.
The electrodes are applied with a d.c. voltage at a predetermined interval monitored or measured by a timer to electrolyze the raw water within the cistern. As a consequence, an appropriate amount of the hypochlorous acid is produced in the raw water with utilization of the chlorine ions in the manner known in the art. The hypochlorous acid serves as an effective chlorine or a component effective in sterilization. Thus, the raw water is sterilized into purified water.
At first, the raw water is reserved as reserved water in the cistern. Next, the d.c. voltage is applied between the electrodes to add the hypochlorous acid in the reserved water. Thus, all of the reserved water is purified into the purified water in the cistern. After that, the purified water is fed from the cistern through a pipe to a terminal unit such as a tap or a dispensing valve of a beverage dispenser.
In the conventional water purifying apparatus, the chlorine generator must be designed so as to be capable of generating a large amount of the hypochlorous acid. This is because all of the reserved water must always be maintained into a purified condition in the cistern. It is therefore difficult to reduce the size of the chlorine generator. This results in inevitable increasing of the cistern in size.